An Aurora dentist is suspected of poisoning his wife to death, police said Sunday.

James Craig, 45, was arrested Sunday morning on suspicion of first-degree murder, Aurora police spokesman Joe Moylan said in a news release. Craig’s 43-year-old wife, who was not publicly identified by police, died early Sunday morning, days after being hospitalized and declared brain dead.

Police say Craig drove his wife to a hospital at about 8:45 p.m. Wednesday because she was suffering from severe headaches and dizziness. Soon after she arrived, her “condition deteriorated rapidly,” and she was put on a ventilator in the hospital’s intensive care unit, Moylan said. She was declared medically brain dead “a short time later,” police said in the news release.

Doctors took Craig’s wife off life support early Sunday morning and she died, Moylan said. Craig was arrested shortly after her death on a warrant for first-degree murder and booked into jail at 2 a.m.

Additional details about the case were not immediately available Sunday. Aurora police Division Chief Mark Hildebrand said in the news release that investigators learned of “suspicious details” in the woman’s death and determined it was “a heinous, complex and calculated murder.”

It was not clear Sunday what poison was used or what evidence led investigators to arrest Craig.

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